# Copyright (c) 2020-present Baidu, Inc. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

INCLUDE(ExternalProject)

SET(GFLAGS_SOURCES_DIR ${THIRD_PARTY_PATH}/gflags)
SET(GFLAGS_INSTALL_DIR ${THIRD_PARTY_PATH}/install/gflags)
SET(GFLAGS_INCLUDE_DIR "${GFLAGS_INSTALL_DIR}/include" CACHE PATH "gflags include directory." FORCE)
IF (WIN32)
    set(GFLAGS_LIBRARIES "${GFLAGS_INSTALL_DIR}/lib/gflags_static.lib" CACHE FILEPATH "GFLAGS_LIBRARIES" FORCE)
ELSE (WIN32)
    set(GFLAGS_LIBRARIES "${GFLAGS_INSTALL_DIR}/lib/libgflags.a" CACHE FILEPATH "GFLAGS_LIBRARIES" FORCE)
    set(BUILD_COMMAND $(MAKE) --silent)
    set(INSTALL_COMMAND $(MAKE) install)
ENDIF (WIN32)

ExternalProject_Add(
        extern_gflags
        ${EXTERNAL_PROJECT_LOG_ARGS}
        GIT_REPOSITORY "https://github.com/gflags/gflags.git"
        GIT_TAG "v2.2.2"
        PREFIX ${GFLAGS_SOURCES_DIR}
        BUILD_COMMAND ${BUILD_COMMAND}
        INSTALL_COMMAND ${INSTALL_COMMAND}
        UPDATE_COMMAND ""
        CMAKE_ARGS -DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER}
        -DCMAKE_C_COMPILER=${CMAKE_C_COMPILER}
        -DCMAKE_CXX_FLAGS=${CMAKE_CXX_FLAGS}
        -DCMAKE_CXX_FLAGS_RELEASE=${CMAKE_CXX_FLAGS_RELEASE}
        -DCMAKE_CXX_FLAGS_DEBUG=${CMAKE_CXX_FLAGS_DEBUG}
        -DCMAKE_C_FLAGS=${CMAKE_C_FLAGS}
        -DCMAKE_C_FLAGS_DEBUG=${CMAKE_C_FLAGS_DEBUG}
        -DCMAKE_C_FLAGS_RELEASE=${CMAKE_C_FLAGS_RELEASE}
        -DBUILD_STATIC_LIBS=ON
        -DCMAKE_INSTALL_PREFIX=${GFLAGS_INSTALL_DIR}
        -DCMAKE_INSTALL_LIBDIR=${GFLAGS_INSTALL_DIR}/lib
        -DCMAKE_POSITION_INDEPENDENT_CODE=ON
        -DBUILD_TESTING=OFF
        -DCMAKE_BUILD_TYPE=${THIRD_PARTY_BUILD_TYPE}
        ${EXTERNAL_OPTIONAL_ARGS}
        CMAKE_CACHE_ARGS -DCMAKE_INSTALL_PREFIX:PATH=${GFLAGS_INSTALL_DIR}
        -DCMAKE_INSTALL_LIBDIR:PATH=${GFLAGS_INSTALL_DIR}/lib
        -DCMAKE_POSITION_INDEPENDENT_CODE:BOOL=ON
        -DCMAKE_BUILD_TYPE:STRING=${THIRD_PARTY_BUILD_TYPE}
)

ADD_LIBRARY(gflags STATIC IMPORTED GLOBAL)
SET_PROPERTY(TARGET gflags PROPERTY IMPORTED_LOCATION ${GFLAGS_LIBRARIES})
ADD_DEPENDENCIES(gflags extern_gflags)

# On Windows (including MinGW), the Shlwapi library is used by gflags if available.
if (WIN32)
    include(CheckIncludeFileCXX)
    check_include_file_cxx("shlwapi.h" HAVE_SHLWAPI)
    if (HAVE_SHLWAPI)
        set_property(GLOBAL PROPERTY OS_DEPENDENCY_MODULES shlwapi.lib)
    endif (HAVE_SHLWAPI)
endif (WIN32)

message(gflag: ${GFLAGS_INCLUDE_DIR}, ${GFLAGS_LIBRARIES})
